A compressor of a refrigeration system is designed primarily for gas compression. However, under some operating circumstances, liquid refrigerant may pass from the evaporator of the system through the suction line and into the inlet of the compressor. If this liquid floodover is substantial, the compressor parts may be damaged due to the incompressibility of the liquid refrigerant with resultant high bearing loads. In addition, the liquid refrigerant may dilute the lubricant contained in the compressor casing with resultant deterioration of lubricity.
In order to solve this problem, it is usual practice to provide a suction accumulator between the evaporator and the compressor having as its primary function the passage of gaseous refrigerant to the compressor and trapping of liquid refrigerant when this liquid is present in excessive amounts. The liquid refrigerant retained by the accumulator is metered to the compressor at a controlled rate such that damage to the compressor and its associated components is prevented.
In other prior art refrigerant accumulators employed in separating liquid refrigerant from gaseous refrigerant, metering holes are provided in the lower portion of the accumulator container wherein oil settling in the lower portion may be returned to the compressor with the gaseous refrigerant. This arrangement, however, allows liquid refrigerant in mixture with the oil to also return to the compressor.
The present invention relates to a heat pump and more particularly to a heat pump comprising a reversible refrigerant circuit including means for controlling the effective charge of refrigerant in the circuit. More particularly, the present invention provides means for separating gaseous refrigerant from a liquid refrigerant and oil mixture and for preventing passage of damaging amounts of liquid refrigerant to the compressor while allowing gaseous refrigerant entrapped with liquid refrigerant to be separated therefrom and returned to the compressor.